1. Field of the Invention
This invention relates to a collapsible seamless aluminum container of the type used for beer, soft drinks, or the like, and more particularly to a container whose annular sidewall can be manually axially collapsed when the container contents are exhausted.
2. Description of the Prior Art
Metal containers of the prior art have been provided with ribs in the container lateral surface extending both horizontally and longitudinally. However, such ribs have been positioned, constructed and arranged to effect only a strengthening function of the lateral surface or sidewall of the metal container. Similarly, metal container sidewalls have also been provided with embossments of varying shapes, but these deformations are generally again only for the purpose of increasing the strength of the container sidewall. Applicant is not aware of any prior art seamless aluminum can or container for accommodating beverages or other goods which is formed of sufficient strength for its intended purpose, and yet can be axially collapsed by manual pressure when exhausted of its contents so that the container will occupy a minimum of space.
In the patent prior art, U.S. Pat. No. 3,401,826 shows a packaging system in which vertical corrugations, horizontal corrugations and diamond-shaped embossments are used to strengthen the sidewalls of a package or container to be formed. The patent discloses light-gauge material which is initially formed in the shape of a flattened tube for shipping purposes, and then containers formed from the tube are expanded, provided with a bottom closure member, filled with the desired contents, and provided with an appropriate cover or lid. No structure is provided in the sidewalls to facilitate axial collapsibility of the container after the contents of the container are removed; in fact, the deformations in the sidewall of the container are stated to be for strengthening the sidewalls.
U.S. Pat. No. 3,472,418 shows annular corrugations in the sidewall of a large drum, which corrugations again are for strengthening the sidewalls.
U.S. Pat. No. 3,089,533 relates primarily to an apparatus for beading thin metal cylinders by passing a ribbed mandrel over the lateral surface of the cylindrical body. Both horizontal and vertical ribs are shown in the lateral surface of the container and the purpose of the ribs is to strengthen the lateral surface of the cylindrical body. The lateral surface is not intended to be axially collapsible.
Prior art U.S. Pat. No. 2,139,143 discloses expressor mechanisms or collapsible devices for dispensing liquids and semi-liquids from sealed containers by applying mechanical screw pressure or pneumatic pressure endwise of the sealed containers to squeeze the container into a collapsed condition so as to empty the contents of the container. In two of the devices which apply rotative screw pressure, the opposite ends of the container being collapsed are rotated relative to each other so that the container walls are collapsed in a spiral fashion. The pneumatic pressure device has a cylinder within which a piston reciprocates to squeeze a container in the cylinder against a stationary head. The container disclosed by the patent is provided with spaced creases which extend intermittently and diagonally or spirally around the lateral surface of the container. Intermittent horizontal creases spaced axially of the container are also diagrammatically shown.